form1.cs

来自「苏金明编写的《用VB.NET和VC#.NET开发交互式CAD系统》一书的源代码」· CS 代码 · 共 139 行

using System;
using System.Drawing;
using System.Drawing.Drawing2D;
using System.Collections;
using System.ComponentModel;
using System.Windows.Forms;
using System.Data;

namespace 拾取
{
	/// <summary>
	/// Form1 的摘要说明。
	/// </summary>
	public class Form1 : System.Windows.Forms.Form
	{
		/// <summary>
		/// 必需的设计器变量。
		/// </summary>
		private System.ComponentModel.Container components = null;

		public Form1()
		{
			//
			// Windows 窗体设计器支持所必需的
			//
			InitializeComponent();

			//
			// TODO: 在 InitializeComponent 调用后添加任何构造函数代码
			//
		}

		/// <summary>
		/// 清理所有正在使用的资源。
		/// </summary>
		protected override void Dispose( bool disposing )
		{
			if( disposing )
			{
				if (components != null) 
				{
					components.Dispose();
				}
			}
			base.Dispose( disposing );
		}

		#region Windows Form Designer generated code
		/// <summary>
		/// 设计器支持所需的方法 - 不要使用代码编辑器修改
		/// 此方法的内容。
		/// </summary>
		private void InitializeComponent()
		{
			this.components = new System.ComponentModel.Container();
			this.Size = new System.Drawing.Size(300,300);
			this.Text = "Form1";
		}
		#endregion

		/// <summary>
		/// 应用程序的主入口点。
		/// </summary>
		[STAThread]
		static void Main() 
		{
			Application.Run(new Form1());
		}

		private  PointF m_preBegin,m_preEnd,m_curBegin,m_curEnd;
		private Module m=new Module();

		private void Draw( Graphics g)
		{
			g.DrawEllipse(Pens.Blue, 50, 50, 200, 200);
			g.DrawLine(Pens.Blue, 40, 80, 300, 200);
		}

		protected override void OnPaint( PaintEventArgs e)
		{
			Graphics g= e.Graphics;
			g.FillRectangle(Brushes.White, this.ClientRectangle);
			Draw(g);
		}

		private void Form1_MouseMove(object sender, MouseEventArgs e )
		{
			Graphics g = this.CreateGraphics();
			Draw(g);
			m_curBegin = new PointF(e.X - 5, e.Y - 5);
			m_curEnd =new PointF(e.X + 5, e.Y + 5);
			g.DrawRectangle(Pens.White, m_preBegin.X, 
				m_preBegin.Y, 10, 10);
			g.DrawRectangle(Pens.Green, m_curBegin.X, 
				m_curBegin.Y, 10, 10);

			//把拾取矩形转换为四条直线段
			CLine[] line1= {null, null, null, null};
			line1[0] = new CLine(m_curBegin, new PointF(m_curBegin.X, m_curEnd.Y));
			line1[1] = new CLine(new PointF(m_curBegin.X, m_curEnd.Y), m_curEnd);
			line1[2] = new CLine(m_curEnd, new PointF(m_curEnd.X, m_curBegin.Y));
			line1[3] = new CLine(new PointF(m_curEnd.X, m_curBegin.Y), m_curBegin);

			Pen pickPen=new Pen(Color.Red);
			pickPen.DashStyle = DashStyle.Dash;

			//拾取直线段
			for (int i = 0;i<=3;i++)
			{
				CLine newline=new CLine(new PointF(40, 80), new PointF(300, 200));
				float[] inter1;
				inter1 = m.LineLine(line1[i], newline);
				if (inter1[0] > 0)
				{
					newline.Draw(g, Pens.White);
					newline.Draw(g, pickPen);
				}
			}

			//拾取圆
			for (int i = 0;i<=3;i++)
			{
				CCircle circle=new CCircle(new PointF(150, 150), new PointF(150, 50));
				float[] inter3;
				inter3 = m.LineCircle(line1[i], circle);
				if (inter3[0] > 0)
				{
					circle.Draw(g, Pens.White);
					circle.Draw(g, pickPen);
				}
			}

			m_preBegin = m_curBegin;
			m_preEnd = m_curEnd;

		}
	}
}